Outside pipe cutter



Dec. 3, 1940. w. L. CHURCH 2,223,984

OUTSIDE PIP GUTER Filed Nv. 1e, 1959 L sin* Mmm Patented Dec. 3, 1940 UNITED STATES-I i PATENT OFFICE This invention relates to an outside pipefcutter.

An object of the invention is to .providefa cutter adapted to be lowered into a wellover a pipe stuck in the well and to cut by rotation whereby the stuck pipe may be cut into sections and withdrawn, a section at a time. Y

The invention herein described' embodies ce1'- tain improvements over outside pipe cutters disclosed in Patent No. 1,855,338 issued April 26, 1932, and Patent No. 1,944,594 issued January 23, 1934, both of said patents having been issued to applicant by the United States Patent Office.

It is another object ofthe invention to provide a cutter adapted to be lowered into a well over `a pipe stuck in the well with a novelV overshot to engage said pipe and whichis effective to grip a string of pipe sections connected together byv tapered or bottle neck joints, which joints do not present a square abutment and cannot be engaged by a conventional grapple.

It is another object of the invention to provide an outside pipe cutter which embodies a novel type of blade guide or shoe which rocks and thereby conforms to the angle assumed bythe knife as the same is being fed to the work.

It is another object of the invention to provideL to the pipe to be cut and consequently the cuttersv are not required to remove as much material from the pipe being cut, during the cutting operation,A

as they would be required to do if! they were mounted on the vertically movable shell or body as is the case with outside cutters now in cornmon use.

With the above and other objects inview, the invention has particular relation to certain novel features of construction, operation and arranger ment of parts, an example of which is given in this specication and illustrated in the accompanying drawing,` wherein:

Figure 1 shows a side view of the cutter partly` in section.

Figure 2 shows a side View partly in section showing the cutter in operative relation Withthe pipe to be cut and showing the cutter blades in active position.

Figure 3 shows a cross sectional view taken on the line 3--3 of Figure 1, and

Figure 4 shows a cross sectional view taken along the line 4-4 of Figure 1.

Referring now more particularly to the drawing wherein like numerals of reference designate similarfV parts in each of the gures, the numeral I designates the tubular cutter body or shell whose upper end is connected to the coupling 2 which in turn is connected to an operating string of pipe as 3 which extends to the 4ground surface. The' lower end of the shell is inwardly thickened and is provided with vertical slots 4 whose lower ends have oscillatable shoes 5 mounted therein on cross pins 6, and forming blade guides. Attached to the lower end of the shell is a conventional type of guide 'I whereby the shell may be guidedover the upper end of the pipe 8 to be cut as the tool is lowered into the well.

Within the shell I is mounted the grapple means which is adapted to engage the pipe 8 which is stuck in the well bore. The cylindrical anchor 9 is pinned in place above the slots 4 by means of a frangible pin I0 of soft metal such as brass, so that it will readily shear as hereinafter explained. The anchor has openings I I therethrough in which are pvotally mounted on the pins I2, I2, the jaws I 3, I3. Each jaw'terminates at one end in a sharp pipe'engaging edge i311` and is bifurcated at the other end forming arms I4, I4 which have aligned bores therethrough to receive the pin I2. Positioned between the arms and around the pins are coil springs I5, I5 which urge the jaws into radial position as shown in Figure 1. Figure 2 shows that the jaws I3, I3, when in en gaging position with the stuck pipe, are almost perpendicular thereto to give the maximum wedging. or gripping effect on the pipe. These jaws will grip the `smooth cylindrical` surface of the pipe and also the tapered or bottle-neck joints I6 thereof. Within the shell I, beneath the cylindricalanchor 9 there is a collar I'I which abuts the lower end of the anchor 9 and swivels relative thereto. Located within the slots 4 are the cutter blade anchors I8 which are somewhat shorter in length then the lengths of the slots 4 and are suitably. secured to the collar I1 `as by means of` set screws I9. The upper ends of the blade anchors I8 have inwardly turned flanges 20 which ride in the external annular groove 2l of the anchor 9 whereby the cutter blade anchors I8 on the collar I1 may rotate with the shell I and swivel aboutthe anchor 9.

Thelower ends of theblade anchors I8 are bifurcated forming ngers I8a, and there are cutters 22 whose upper ends are pivoted between these fingers on the pins 23. The outer sides of it l the lower ends of these cutters are beveled as at 24 and ride on the correspondingly beveled guide shoes 5 beneath. It is noted that the lower end of each slot 4 is reduced in width as at 4a and the cutter blades t snugly in these reduced lower ends so as to give said blades lateral support, the lower ends of the blades terminating in sharp cutting edges 22a. As shown in Figures 1 and 2 as the cutter blade 22 is rotated inwardly, the angle of the beveled portions of the blade relative to the shell or body I will vary. The shoe 5 is rotated so that a large bearing area between the shoe and the face of the bevel portion is maintained. The large bearing area will reduce the bearing stress on the shoe so that there will be no surface distortion of the shoe whereby the feed of the cutters to the work will be continuous and smooth.

The tool is assembled as shown in Figure 1 with the anchor 9 pinned in place by the pin I0 and with the cutter blades 22 in upper, or inactive, position. As so assembled the tool is let down into the well bore and is guided over the inside pipe S to be cut, the inwardly inclined jaws I3, I3 readily passing over the outside couplings I5 of the pipe 8. When the cutting tool is lowered to a point at which it is desired to make the cut, an upward pull is exerted on the operating string I3, causing the sharp edges I 3a of the jaws I3 to engage the pipe 8. A further upward pull will cause the pin IEB to shear but the jaws I3 will hold the anchor 9, the collar I'I and the cutter blade anchors I8 as well as the cutter blades 22 against upward movement; in other words, the cutter blades 22 will be held against longitudinal movement relative to the pipe 8, while the outer shell or body I is moved upwardly. At the same time the body or shell I is being moved upwardly, the tool will also be rotated. The shoes 5 contacting with the inwardly beveled lower ends 24 of the cutter blades will Ygradually force said blades inwardly while the tool is being rotated and the cutter edges 22a will be gradually forced into and sever the pipe 8.

It will be noted that very little of the material of the pipe being cut will be removed while making the cut owing to the fact that the cutter blades 22 move inwardly only and do not also move longitudinally of the pipe being cut as is the case in cutters of this type now in common use.

When the pipe has been severed the cut off section may be pulled out with the tool as it is removed from the bore, the jaws I3 being of sufcient strength for this purpose.

The drawing and description disclose what is now believed to be a preferred form of the invention only while the broad principle of the invention will be deiined by the appended claims.

What I claim is:

1. An outside pipe cutter adapted to cut by rotation and comprising an outer shell adapted to work over the pipe to be cut, a cutter blade anchor mounted in the shell, a blade pivoted to the anchor, means in the shell engageable with the pipe to be cut and arranged to hold said anchor against longitudinal movement relative to the pipe being cut during the cutting operation, said shell being movable longitudinally relative to said pipe and anchor during the cutting operation, said cutter blade and shell having coacting parts which include a shoe mounted in the shell and having va substantially flat face which bears against the outer face of the cutter blade and effective to move the cutter blade in wardly into cutting relation with the pipe upon longitudinal movement of the shell, said shoe being pivotally mounted whereby the shoe will pivot as the angle of the cutter blade is varied.

2. An outside pipe cutter shaped to be lowered into a well over a pipe to be cut and adapted to be cut by rotation and comprising a shell, a cutter blade anchor in the shell, a cutter blade pivoted to the anchor, grappling means including a y.pivotally mounted jaw adapted to grip the outer smooth surface of a pipe and `yieldable means urging the jaw in contact with said pipe to hold said anchor against longitudinal movement relative to the pipe being cut during the cutting operation, said shell being movable longitudinally relative to said pipe and anchor during the cutting operation, said cutter blade and 1 shell having coacting parts which are eiective to move .the cutter blade inwardly into cutting relation with the pipe upon longitudinal movement of the shell.

3. An outside pipeA cutter shaped to be lowered into va well over a pipe to be cut and adapted to be cut by rotation and kcomprising a shell, a cutter blade anchor in the shell, a cutter blade pivoted to the anchor, grappling means including a pivotally mounted jaw and yieldable means urging the jaw into contact with said pipe to hold said anchor against longitudinal movement relative tothe pipe being cut during the cutting operation, said shell being movable longitudinally relative to said pipe and anchor during the cutting operation, said cutter blade and shell having coacting parts which include a shoe mounted in the shell and having a substantially plane bearing face adapted to bear against the outer face of the cutter blade and effective to move the cutter blade inwardly into cutting relation with the pipe upon longitudinal movement of the shell, said shoe being pivotally mounted whereby the shoe will rotate as the angle of the cutter blade is varied.

4. In an outside pipe cutter, a tubular shell having a slot, a cutter anchor mounted for longitudinal movement relative to the shell, a cutter in the slot and mounted to rotate on the anchor a cutter guide in the slot having a substantially flat face in contact with the outer side of the cutter and mounted to pivot to maintain said contact approximately throughout the cutter movement.

5. In an outside pipe cutter, a tubular shell having a slot, a cutter anchor mounted for longitudinal Amovement relative to the shell, a cutter in the slot and mounted to rotate on the anchor, a cutter guide in the slot whose surface conforms in shape to and is in contact with the outer side of the cutter and mounted to pivot to maintain said contact approximately throughout the cutter movement.

6. In an outside pipe cutter, a tubular shell, a cutter mounted in the shell, a cutter anchor mounted for longitudinal movement relative to the shell and effective upon said movement to actuate the cutter into cutting position, grappling means in the shell engageable with a pipe to be cut and arranged to hold said anchor against longitudinal movement relative to the pipe being cut during cutting operation including a pivotally mounted jaw whose free end is formed to grip the smooth surface of a pipe and yieldable means urging the jaw in contact with said pipe.

WALTER L. CHURCH. 

